Notes:Prior to the distinction between Earth-1 and Earth-2, the characters had a shared history in a Batman character that existed on an "undefined" Earth. Contrary to popular belief, not all Golden Age stories are automatically Earth-2, but exist as a shared history between Earth-1 and Earth-2 characters. The first clear appearance of the Earth-1 Batman was Detective Comics #327 and the first appearance of the Earth-2 Batman was Justice League of America #82. The Batman that was a member of the Justice League of America will be considered to be the Earth-1 Batman since the JLA is clearly an Earth-1 concept.

Meets Commissioner Gordon face to face for the first time in Batman #7 The Trouble Trap! (Oct-Nov 1941).

Commissioner Gordon appoints Batman an honorary member of the Gotham Police Department in "The People Vs. The Batman" (Oct-Nov 1941).